Tariffs have gone from a dry subject in economics textbooks to one of the biggest drivers of markets in recent years. A single announcement can move currencies, stock indices and commodity prices within minutes. Yet the basic idea is simple: a tariff is a tax on goods that cross a border.
What a tariff is
A tariff is a charge that a government places on imported goods. It can be a percentage of the value of the goods, known as an ad valorem tariff, or a fixed amount per unit, such as a set charge per tonne. The importer pays it to the government when the goods arrive.
Governments use tariffs for several reasons: to protect domestic industries from foreign competition, to raise revenue, to put pressure on other countries in trade disputes, or to support national security in strategic industries such as steel or chips.
Who really pays
The importer writes the cheque, but the cost is often shared. Some is passed on to customers through higher prices. Some may be absorbed by the importer through lower profit margins. And some may be absorbed by the foreign exporter, who cuts prices to stay competitive. How the burden is split depends on how easily buyers can find alternatives and how much pricing power each side has.
Studies of recent tariff rounds have generally found that a large share of the cost ended up with domestic businesses and consumers rather than foreign producers.
How tariffs move markets
Tariffs can push up inflation, because imported goods and the products made from them become more expensive. That can affect interest rate expectations and bond yields. They can also weigh on economic growth by disrupting supply chains and reducing trade.
Currencies often react quickly. A country hit by new tariffs may see its currency weaken, as investors expect lower exports. Companies that rely heavily on imports or exports can see their shares move sharply, as can sectors such as carmakers, retailers and manufacturers with complex global supply chains.
Cutting tariffs
Tariffs can move in the other direction too. Governments sometimes suspend or remove tariffs on certain goods to ease cost-of-living pressures, as the UK has done on some food imports. The effect on prices is usually modest and can take time to reach shop shelves, because retailers and suppliers decide how much of the saving to pass on.
What traders watch
Traders follow announcements from governments, the timing of when tariffs take effect, any exemptions, and retaliation from trading partners. They also watch company results for comments on how tariffs are affecting costs and demand. Our guide to how oil prices feed into UK petrol prices offers a similar look at how costs travel to the consumer.
The bottom line
A tariff is a tax on imports. Who ends up paying it, and how much it moves prices, depends on the details, but tariffs can shift inflation, currencies and company profits, which is why markets react so strongly to them.
Policy headlines can catch traders off guard. If you want to see how prepared you are, try the free Samuel & Co Trading Trader Assessment.
